The present invention relates to a bulk material feeder constituted such that, in particular, a cleaning mechanism of a loader inside is provided inside the feeder. The invention is related to a bulk material feeder (in general referred to as loader) used to supply plastic materials for molding, in an adequate quantity, to a plastic molding machine.
In carrying out the plastic molding, it is widely known to employ a bulk material feeder, called, in general, a loader, as a unit to feed materials for molding to a molding machine.
The above-mentioned bulk material feeder is known to be public and is combined with a plastic molding machine, concretely, as exemplified in FIG. 9.
Such units are constituted by an aspirator, composed of a filter 1 and a blower 2, a molding machine 3 and a material hopper 4, a target tube section 5, a bulk material quantity detection sensor 6, a cyclone separator 7 and, a material tank 8, etc., as a bulk material feeder.
The filter 1 and the cyclone separation 7 of the above-mentioned aspirator are linked by a suction pipe 11, and the cyclon 7 and the material tank 8 are linked by a transportation piping 12.
The above-mentioned equipment operates as follows:
First, negative pressure is formed in the section of the cyclon 7 through the section pipe 11 by driving the blower 2 installed in the aspirator.
Resin pellets 9 as plastic material are aspired and transported, together with the air, through the transportation piping 12, and reaches the section of the cyclone separator 7.
Resin pellets 9 are aspired from the material tank 8 together with the air, since they have proper weight. The pellets are separated from the air in the cyclone separator 7, dropped, stored in the material hopper 4 on the molding machine 3 through the target tube section 5, and continuously fed to the molding machine in the required quantity.
The supply quantity control of resin pellets 9 is carried out by supervising the resin pellet quantity in the target tube section 5 with the sensor 6. Part of the raw pellets used is micronized by an impact at the time of supply, or for other reasons. This part of the raw pellets adheres to internal walls of the hopper, resulting in not easily attaining the object of changing of resin materials used by only supplying and transporting new resin material pellets.
As a means to cope with these problems, conventionally, as exemplified in FIGS. 9 and 10, many operations to dismantle the section of the hopper 4, where fines of raw materials adhered to internal walls of the hopper, are required, and, using an air gun 10, fines of resin adhered must be blown off by blowing pressurized air on the hopper walls or the surface coated with raw resin must be wiped off and cleaned manually.
In case such a measure is taken, however, in a large-sized molding machine, the dismantling and cleaning work required for the equipment is not easy.
In particular, in terms of the equipment construction, there are many places where scaffolding is not good, and so on, and a long time is also required for the cleaning work. Also, during cleaning work, the molding work must be stopped. Further, effective cleaning is not often able to be expected.
Besides, in case the pressurized air is jetted out so as to produce an excessively strong air current, causing strong pressure, static electricity is generated inside the hopper. Moreover, there are also difficult points because of the adhesion of fines to the inside of the hopper, and so on, and there is a limit also in the rise of air pressure.